Abstract: Residents, as key stakeholders in ecosystem protection and utilization, play a crucial role in shaping environmental governance and ecological restoration. Understanding their attitudes and preferences towards ecosystem services provides valuable insights for informed decision-making. This study, based on survey data collected through face-to-face interviews, focuses on the case of the Xiaohai Lagoon in Hainan Province. Using Importance-Satisfaction Analysis and correlation methods, the research investigates local residents’ perceptions of 13 major ecosystem services provided by the lagoon and explores their trade-offs and synergies. The results indicate that residents’ perception of the importance of provisioning services (I_es=−1.53), cultural services (I_es=0.18), and regulating and maintaining services (I_es=0.36) increases in this order. Satisfaction levels are highest for cultural services (S_es=0.37), followed by regulating and maintaining services (S_es= 0.06), with provisioning services receiving the lowest satisfaction (S_es=−1.09). Disaster control and recreational ecosystem services were identified as key areas for improvement, followed by pest control, air quality regulation, and place attachment, where service provision currently fails to meet residents’ needs. There is a general synergistic relationship between the perceived importance and satisfaction of ecosystem services, with income sources and education levels identified as significant influencing factors. These findings provide essential technical support for future environmental governance and ecological restoration of the Xiaohai Lagoon.